Removable liner for centrifugal pumps



Filed Feb. 25, 1924 E N MACKLEY REMOVABLE LINER FOR CENTRIFUGAL PUMPS July 14, 1925.

V lllllllllll l i L EDWARDNMAcKLEv,

ATTORNEY:

IPATENT OFFICE EDWARD N. MACKLEY, OF NEWCASTLE-UPON-TYNE, ENGLAND.

REMOVABIE LINER FOR CENTRIFGAL PUMPS.

Application 11nd February 25; 1924. i serial 1ro. 694,961.

To all whom, it may concern:

Be it known that I, EDWARD NORMAN Maenner, Britain and Ireland, residing at 55 Wingrove Road, in the city and county of Newcastle-upon-Tyne, England, have invented certain new and useful Improvements in Removable Liners for Centrifugal Pumps, of which the following is a specification, reference being had therein to the accompanying drawing.

This invention relates to centrifugal pumps of the kind having a fixed outer casing, usually of cast iron, fitted with a removable liner which constitutes the voluteshaped guide passage surrounding the impeller or wheel, said liner having portions extending inwards on each side of the impeller in close proximity thereto. The object of my invention is to provide an improved construction of removable liner of this type. A liner in accordance with this invention is characterized in that the side portions provide bearing surfaces for both the eye portion and the hub of the impeller, said side portions being axially withdrawable with the liner and the impeller from the outer casing. The inwardly-extending portions may be separate from the volute-shaped guide passage, in which case they are attached by external bolts around their peripheries to anges around said voluteshaped guide passage; or the volute-shaped guide passage may be made in halves each half having an integral inwardly-extending portion, said halves being connected together by external bolts passing through abutting eripheral flanges around the liner.

I will fully describe my invention with reference to the accompanying drawings wherein Figure 1 is a verticalsection of a centrifugal pump fitted with a-liner having inward extensions in accordance therewith; and Figures 2 and 3 are a vertical section and a sideelevation respectively ofthe liner removed from the casing. Figures 4, 5 and 6 are similar views to Figs. 1, 2 and 3 respectively illustrating a modified construction.Y

Referring to the drawings, inthe example illustrated in Figs. 1, 2 and 3, a is the removable liner which is shaped as usual to form the volute-shaped casing or guide passage for the impeller b' of the pump. In this example, the liner is in one integral part and is not positively secured to the a subject of the King of Great outer casing c. d, d are the inward extensions of the liner which are in the for-1n of separate rings of suitable shape secured by external bolts e around their peripheries'to flanges f around the liner. The extensions d are 1n close proximity to and partially enclose the impeller b. The inner edge of one of the side portions d of the -liner provides a bearlng surface g for the eye portion of the impeller b and an .internal shoulder around the other sideV ortion provides a bearing surface h for a aterally-projecting fiange m around the hub of the impeller, the inner edge d lof the latter side portion engaging an internal flange c of the outer casing. .The space around the impeller is thus restrlcted and iuid leaking between the liner and the lmpeller is confined to said restrictedspace. The side portions d form the only bearmg surfaces for both the eye and the hub of the impeller. As the extensions d become worn t ey can be readily removed and new extensions fitted, wear on the outer castlron casing c being entirely eliminated.

In the modified construction illustrated in Figs. 4:, 5 and 6, the liner-a and its extensions d are made in integral halves connected together by external bolts j passing through abutting peripheral anges ,7c around the liner. Otherwise this construction is exactly similar to that shown in Figs. 1, 2 and 3.

It will be seen that the bolts e and y', being outside the water passages, are not hable to erosion due tothe grit in the water. Moreover the liner and its extensions are not bolted to the outer casing c and can be readily withdrawn axially therefrom with the impeller when the cover n of the casing 1s removed. v

What I claim as my invention, and desire to secure by Letters Patent is 1. A centrifugal pump comprising an outer casing and an 1mpeller, a removable cover for said casing, and a removable liner within said casing comprising a voluteshaped guide passage vsurrounding the impeller of the pump and inwardly-extending portions on each side of the impeller .in close proximity thereto, saidside portions forming the only bearing surfaces for both the eye portion and the hub of the impeller and being axially withdrawable with the liner and the impeller from the outer casing.

2. A removable liner for a centr1fugal pump comprising a volute-shaped guide passage surroundin the impeller of the pump,

- inwardly-extendlng p rt1ons on each Vside of the impeller in close proximity thereto, the inner edge of one of said side portlons forming the" hearing for the eye portion of the impeller, a laterally projecting flange around the hub of the impeller, an internal shoulder around the other of said side portions forming the bearing for said laterally projecting flange and an internal flange on the outer casing of the pump, the inner edge of the latter side portion engaging said internal flange, said side portions beine' axlally withdrawn-ble With the liner and the impeller from the outer casing.

3. A removable liner for a centrifugal pump comprising a volute-shaped guide passage' surrounding the impeller of the pump,

flanges around said guide passage, separate inwardly-extending portions on each side of the im eller in close roximity thereto, external olts around t e peripheries of said side portions attaching them to the flanges of said guide passage, said side portions forming the aring for the eye portion of the im eller, a laterally projecting flange around t e hub of the impeller an internal shoulder around the other of said side portions formin the bearing for said laterally projecting ange and an internal flange on the outer casing of the pump, the inner edge of the latter side portion engaging said internal flange, said side portions being axially Withdrawable with the liner and the impeller from the outer casing.

In testimony whereof I affix my signature.-

EDWARD N. MACKLEY.

the inner edg; of one of 

